1. Field of the Invention
This invention relates to a structure of seat back with armrest for a vehicle or automotive seat which has an armrest storage portion, and a method for forming such seat back structure.
2. Description of Prior Art
Normally, a bench seat and split seat used as a rear seat in an automobile are provided with a movable armrest in the central area thereof, so that the armrest may be moved to a use position for the purpose of supporting arms of passengers sitting on the seat and comforting the passengers in a relaxed posture. For instance, the bench seat typically has a recessed or cut-out region formed centrally of its seat back, which creates an armrest storage portion for allowing the armrest to be stored therein.
Conventionally, to form this kind of seat back with armrest storage portion, it has been a common practice to prepare a covering material including four cut sections defined centrally thereof and a foam padding shaped in a predetermined seat back configuration, the foam padding having a through-hole formed therein. The covering material is merely placed upon the foam padding by anchoring the terminal ends of covering material to a frame or support means in the foam padding. In particular, the afore-said four cut sections of covering material are inserted into the through-hole of padding and anchored via hog rings or the like to an insert wire embedded in the padding around the through-hole, to thereby define an armrest storage portion in the seat back. Then, an armrest is rotatably secured in such armrest storage portion, such that the armrest may be rotated and stored in the armrest storage portion, when not in use.
However, in that conventional method, the anchoring of the covering material has been found defective in creating an undesired plural floated or slacked points and wrinkles in the anchored portions of covering material within the armrest storage portion. Moreover, in the process of forming the foam padding, a foaming die member can not be easily removed from the through-hole of foamed work. That is, during foaming process, the through-hole is formed in the padding by a corresponding shape of projected part of foaming die member, with the result that a close contact between the through-hole and projected part of die member makes removal of the die member from the resulting formed padding difficult.